In general, lamps for a vehicle are widely classified into a headlamp which is installed at a front side of a vehicle, and a tail lamp which is installed at a rear side of the vehicle. The tail lamp performs functional roles, such as a brake operation display, a direction display, or an alarm display, and also performs an aesthetic role for forming an image of a rear side of a vehicle. Considering the situation in which importance of a design of a vehicle in a product value of a vehicle is gradually increased, aesthetic appearance of the tail lamp may be a very important factor in improving a product value of a vehicle.
However, a general tail lamp has a simple configuration including a bulb that is a light source, and a reflector that reflects light of the bulb. For this reason, there is a problem in that shapes of lighting images of the tail lamp are unified. Therefore, a method of increasing aesthetic appearance of lighting images by installing a plurality of light sources such as LEDs has been proposed, which leads to a problem in that a large number of light sources are required.
A demand for surface emission images utilizing indirect reflection rather than the lighting images configured to have a multi-dot shape has been increased due to an increase in an index of emotional quality of a consumer.
However, because optical efficiency of the surface emission images is low, there are problems in that it is difficult to satisfy regulations on visible angle light distribution, and a stereoscopic effect of the lighting images is insufficient.